WikiLeaks founder Julian Assange on Tuesday was granted a hearing with the Swedish Supreme Court, where his lawyers will appeal to lift an arrest warrant against the whistleblower which has kept him confined to the Ecuadorian embassy in London under political asylum since June 2012.

Assange has repeatedly argued that extradition to Sweden will allow him to be sent to the U.S., where he faces espionage and conspiracy charges for his role in publishing a cache of military and State Department documents in 2010. Former army intelligence analyst Chelsea Manning is currently serving 35 years in prison at Fort Leavenworth, Kansas for her part in the leak.

Assange has also said that his confinement to the embassy, now approaching three years, is a violation of Article 5 of the European Convention on Human Rights, which guarantees fundamental liberty and security of person.

The court's decision on Tuesday was a turnaround from a previous appeal court ruling in November, which found that lifting the warrant would risk allowing Assange to flee legal proceedings and that his confinement to the embassy was self-imposed.

The arrest warrant against Assange stems from sexual assault allegations in Sweden, although he has not been formally indicted with any crime. Marianne Ny, the prosecuting attorney in the case, has repeatedly denied requests to interview Assange at the embassy, which observers say may have been the catalyst for changing legal opinion in Sweden on Assange's fears of extradition.

In its decision on Tuesday, the court remarked on "the issue of the conduct of investigations and the principle of proportionality."

Earlier this month, government documents acquired by the Electronic Privacy Information Center (EPIC) through a Freedom of Information Act request revealed that the FBI and the U.S. Department of Justice are continuing an "ongoing criminal investigation of WikiLeaks."

In response to the ruling, WikiLeaks wrote on Twitter:

Note that our US case continues and the UK says they will arrest #Assange anyway, even if the Swedish extradition warrant drops.

— WikiLeaks (@wikileaks) March 10, 2015